General Arkibald Mater -Grim
 He runs The Academy at Sanctum Trisane. He is also one of the poster children for the earlier generation Custos. As a result of his continued action, he is a permanent paraplegic. It does not change his ability to lead, nor his expansive knowledge on the does of humanity. It also does change his lethality if one doubts his ability.

He still answers to his Custo tag of Grim.